Multi-photon processes in quantum imaging: Classical light versus time-frequency entanglement

Date: 
Monday, April 16, 2007 (All day)
Speaker: 
Dr. Ashok Muthukrishnan
Speaker's Institution: 
Swarthmore College

We discuss some results that pertain to the preparation and measurement of photons that lead to sub-wavelength features in optical interference. Recent developments such as quantum imaging, quantum lithography, and quantum microscopy are examined in light of these results. A central theme of the talk will be to study and contrast the effects of classical light (laser source) and time-frequency entangled light. The talk will focus on three topics. First, we will show that sub-wavelength interference lithography in two dimensions can be achieved with nonlinear, direction-selective photo-absorption, and thus, without requiring a quantum source of light. Second, we will examine two-photon absorption by two independent atoms as a model for understanding the (non-classical) linear intensity scaling of an entangled photon source, such as a three-level cascade decay. Lastly, we will focus on some recent work that hints that anti-bunching in two-photon correlations from a doubly driven Raman source can be used to enhance microscopic resolution of one atom from its neighbor below the Rayleigh limit.